There is a growing trend in the utility industry to convert existing coal-fired power plants to burn other fuel types, such as biomass and natural gas, though whether such conversions are environmentally beneficial remains controversial. This trend is driven by a number of factors, including state-level renewable portfolio standards; federal incentives and looming environmental regulations; consumer demand and environmental awareness; and an economic climate that is making coal less attractive.[1] Although conversion costs can be expensive, utilities already have the facilities sited and water supply and transmission lines established. Converting existing facilities can often cost less than installing the emissions control systems required to keep an antiquated coal plant running.[2]

Biomass conversions

The majority of conversion projects to date are centered on switching to biomass fuel sources. Biomass generally includes any organic material that is not a fossil fuel. The National Renewable Energy Laboratory (NREL) defines biomass as "any plant-derived organic matter. Biomass available for energy on a sustainable basis includes herbaceous and woody energy crops, agricultural food and feed crops, agricultural crop wastes and residues, wood wastes and residues, aquatic plants, and other waste materials including some municipal wastes."[3]

Support for biomass within the environmental community is mixed, and there are no easy generalizations about its environmental pluses and minuses. Supporters identify biomass as an improvement over coal, touting benefits that include significant reductions in the emissions of sulfur dioxide, nitrogen oxides, and mercury. In addition, biomass materials are often described as "carbon-neutral," because they release the same amount of carbon when burned as they remove from the atmosphere while growing. In theory, the CO2 released during the combustion of biomass materials will be recaptured by the growth of these same materials, creating what is described as a "closed-carbon cycle".[4] Fossil fuels, by contrast, emit vast quantities of carbon dioxide that were captured through photosynthesis millions of years ago and would otherwise remain trapped underground.[5]

However, many environmentalists are firmly against the use of biomass to offset coal-generated power. Critics point out that no combustion technologies actually mitigate greenhouse gas emissions, and that the focus of a new energy policy should be on energy conservation and zero-emissions technologies like wind and solar.[6] Further, while biomass technologies may be touted as carbon-neutral, in practice this may not be the case. Studies suggest that in reality, the carbon released by burning would take decades to remove from the atmosphere, because of the length of time necessary to replenish harvested tree and plant material and re-sequester the equivalent amount of CO2.[7]

Biomass also presents other issues. In terms of emissions, it releases approximately the same amount of particulate matter as coal and fifty percent more carbon monoxide and carbon dioxide[citation needed]. A Massachusetts study found that 135MW of biomass energy generation would produce 482 tons of nitrogen oxides, 617 tons of carbon monoxide, 165 tons of particulate matter, and 2.2 million tons of CO2.[7] The cultivation and clearcutting of biomass materials on a large scale also bear major implications for wildlife habitats, biodiversity, water supplies, as well as a potential depletion in the terrestrial carbon sink.[8][9] Ecologists point out that even using waste wood or so-called marginal lands would still disrupt natural habitats. For biomass to be an effective energy source on a large scale, it would have the potential to "decimate biodiversity in an attempt to save the planet," according to ecologist Mike Palmer of Oklahoma State University.[10] Ultimately, critics argue that the environmental impacts of biomass are not well enough understood to justify moving forward with large-scale projects, and that in fact there may be disastrous implications for any significant reliance on biomass power generation.

In June 2010 a six-month study commissioned by Massachusetts state environmental officials was released and found that biomass-fired electricity would result in a 3 percent increase in carbon emissions compared to coal-fired electricity by the year 2050 if those trees were harvested in New England forests. The study's authors arrived at the 3 percent figure by comparing how much carbon is emitted into the atmosphere through the burning of wood, called "carbon debt", with the amount of carbon removed from the atmosphere from the regrowth of trees, or "carbon dividends." The study made a series of recommendations, which included forcing currently operating biomass facilities to report where they get their supply of wood and requiring them to purchase wood from forests with approved forest management plans.

The report also recommends additional environmental protections at locations where trees are being cut down for biomass plants, including "requiring enough coarse woody debris is left on the ground, particularly at nutrient poor sites, to ensure continued soil productivity, as well as sufficient standing dead wildlife trees remain to promote biodiversity."[11]

Natural gas conversions

Although some coal-fired power plants are reported to have been converted from coal to natural gas, a 2010 study by the Aspen Environmental Group for the American Public Power Association reports that such "conversions," when examined, are replacements rather than retrofits:[12]

The electricity industry can theoretically switch to natural gas either by retrofitting existing coal-fired units to burn natural gas or by closing the coal plants and building new gas-fired plants. Aspen’s research uncovers no instances of coal plant retrofits to natural gas and, in fact, virtually all of the public references to conversion of coal to natural gas or repowering turn out instead to be replacements. The reason is economics. Even the U.S. Government Accountability Office (GAO), when it looked at this issue switching the Capitol Building power plant to natural gas, noted that not only was switching all U.S. coal-fired generation infeasible due the gas supply and infrastructure required, but that it would be more cost-effective to construct new gas-fired units than to retrofit existing coal-fired units to burn natural gas. Combined-cycle gas-fired generation costs roughly $1 million per MW, installed.

The environmental impacts of natural gas are better understood than those of biomass. Natural gas combustion produces almost 45 percent fewer carbon dioxide emissions than coal, emits lower levels of nitrogen oxides and particulates, and produces virtually no sulfur dioxide and mercury emissions. The lower levels of these emissions mean that the use of natural gas does not contribute significantly to smog or acid rain formation. In addition, because natural gas boilers do not need the scrubbers required by coal-fired power plants to reduce SO2 emissions, natural gas plants create much less toxic sludge. [13]

However, natural gas is still a fossil fuel. Although its carbon content is lower than that of coal, it nonetheless releases harmful CO2 into the atmosphere when burned.[14] Its extraction from shale, the most significant new source of natural gas, can have harmful impacts on water, land use, and wildlife, if the process is not managed properly. As with biofuels, many enviromentalists do not see natural gas as a longterm solution for the nation's fuel needs. In July 2009, Robert F. Kennedy Jr. published a column acknowledging the "environmental caveats" that come with converting coal plants to natural gas. He and other environmental advocates, however, do support natural gas as a short-term solution to reduce the environmental burden of coal until renewable solar, wind, and geothermal technologies can be implemented to their full potential.[15]

Although natural gas combustion produces lower greenhouse gas emissions than coal, leakage of natural gas during production and transport may have significant greenhouse gas effects. Natural gas is composed mainly of methane, a greenhouse gas far more potent than carbon dioxide when released into the atmosphere. Methane in the atmosphere is eventually oxidized, producing carbon dioxide and water. In the atmosphere methane has a half life of seven years (if no methane was added, then every seven years, the amount of methane would halve). The radiative forcing of methane is 72 times that of carbon dioxide (averaged over 20 years) or 25 times that of carbon dioxide (averaged over 100 years).[16]Carbon dioxide receives the lion's share of attention over greenhouse gases because it is released in much larger amounts. Still, it is inevitable in using natural gas on a large scale that some of it will leak into the atmosphere. Current USEPA estimates place global leakage of methane at 3 trillion cubic feet annually[17], or 3.2% of global production[18]. Direct emissions of methane represented 14.3% of all global anthropogenic greenhouse gas emissions in 2004 [19].

It was reported in July 2012 that for the first time ever natural gas power generation in the United States matched the power generated by coal. Coal and natural gas generation by both provided approximately 32% of total monthly generation for the U.S, according to U.S. Energy Information Administration.[20]

Coal plant conversion projects

Below is a list of existing, in progress, and proposed coal plant conversion projects.

As of March 2009, when Georgia Power announced state approval to convert its Mitchell plant to biomass, Alabama Power, another Southern Company affiliate, was also considering a switch to biomass at its coal-fired Gadsden and Barry plants. By 2011 the Gadsden plant had the capability to produce steam and electricity using coal or natural gas, or both, and by 2011 was using mainly natural gas. The plant also was an experimental site for burning wood biomass and switch grass fuels, but as of 2012 the plant does not burn biomass.[21]

In May 2012, Alabama Power disclosed that it plans to have its four smaller generating units at Gaston Steam Plant, representing 1,000 megawatts, converted to run on natural gas by 2015. The project will involve building a gas pipeline to tie into the Transcontinental pipeline, about 30 miles south of the plant. Gaston's largest unit, 880 megawatts, will remain coal-fired. That unit has pollution control devices, and will likely require additional measures to meet new standards of mercury and other air toxics.[22]

In August, 2009, Tennessee Valley Authority President Tom D. Kilgore said that TVA is studying whether it should close its John Sevier Fossil Plant near Rogersville, Tenn., and the oldest six units of the Widows Creek Fossil Plant near Stevenson, Alabama. A federal judge has ordered TVA to install pollution equipment on the plants by the end of 2013, at an estimated cost of more than $1 billion. However, the company has not yet budgeted any money for the improvements. In 2010 TVA is planning to begin building an $820 million gas-powered plant to replace the generation at its John Servier Plant. It is unclear whether TVA will convert any of the plants to other fuel sources.[23] The agency has already reduced power production from the oldest six units at Widows Creek. Environmental groups want TVA to shut down or convert to cleaner fuels the oldest and least efficient of its coal plants, including Widows Creek, John Sevier, and Johnsonville plants.[24]

On April 14, 2011, TVA and North Carolina settled a 5-year-old lawsuit - North Carolina v. TVA - over TVA emissions from its coal-fired plants. As part of the agreement, TVA agreed to phase out 18 units of its coal plants, including six units at the Widows Creek Fossil Plant, taking all but two offline.[25][26] In May 2012, TVA began considering a switch to natural gas for the plant, linked up to a proposed natural gas pipeline from Tennessee through Alabama to Georgia.[27]

California: Mt. Poso Cogeneration Plant

Mt. Poso Cogeneration Plant is currently being converted to burn 100% biomass - agricultural and residential green waste from nearby areas. The conversion is expected to be completed by Sept. 2010.[28]

In August 2008, Colorado regulators approved Xcel Energy’s plan to shut down two coal plants: the Arapahoe Station (Denver) and the Cameo Station (east of Grand Junction). According to Western Resource Advocates, "The utility’s decision to shut down the plants has been praised as the nation’s first voluntary effort to cut coal power generation in an attempt to reduce greenhouse gas emissions. In its decision to support Xcel’s plan, the Colorado Public Utilities Commission (PUC) cited public health benefits and shared concerns about carbon emissions as major selling-points in the company’s groundbreaking proposal. The verdict marks a collective effort to move the state and its utilities toward the carbon reduction goals outlined in Governor Bill Ritter’s Climate Action Plan."[29]

Xcel plans to replace the combined 229 MW of coal power with 850 MW of wind power and a 200 MW utility-scale solar power plant with storage capacity by 2015. Another key component of Xcel’s proposal, to build a 480 MW natural gas plant at the Arapahoe station, has been postponed pending approval by the Colorado PUC.[29]

Xcel and the City of Boulder are in negotiations to renew Valmont Station's contract with the city. The agreement must be renewed every five years and is slated to expire in August 2010.[30] Many Boulder residents are pushing for the plant to stop burning coal and either shut down entirely or convert to biomass fuels, such as beetle-killed timber, forest slash, and invasive shrubs.[31][32]

On July 14, 2009, the Colorado Air Quality Control Commission held a hearing to solicit public comment on renewing the plant's permit. More than 200 people attended a rally before the meeting to oppose allowing the plant's continued use of coal. About 50 people addressed the Commission, asking its members to deny the permit because the plant emits more than 1 million metric tons of carbon dioxide each year.[33]

On November 22, 2011, NRG Dover said the 18MW Dover Municipal Power Plant will be converted to natural gas by May 2012, funded through a state-assisted, $26.5 million project of the Energy Efficiency Investment Fund.[34]

In 2011 Florida Power (an affiliate of Arroyo Energy and JPMorgan Chase) proposed to convert the Central Power & Lime Power Plant in Brooksville, Florida from a 150 megawatt coal power plant to a 70 to 80 MWg woody biomass-fueled power plant. The project will require internal structural modifications to the pulverized coal boiler to convert it to a biomass-fired grate-suspension boiler. The existing steam turbine electric generator will be retained to generate electrical power. On December 16, 2011, the Florida DEP gave notice of its intent to issue an air permit for the project.[36]

On March 19, 2009, the Georgia Public Service Commission approved a request from Southern Company subsidiary Georgia Power to convert the coal-fired Mitchell Steam Generating Plant to burn surplus wood waste. When the transition is completed, Mitchell will be the first biomass plant in Southern Company's fleet and "the largest biomass facility in the United States" at 96 MW, according to COO Tom Fanning.[37]

In March 2010 school director Ken Crowe stated that biomass may be in the coal plant's future. "There is a lot of discussion about what we will do with the coal plant over the next 10 years,” Crowe said. “We have had at least one major study that basically asked the question, if we were going to replace it with something that was a more renewable fuel source, what are the most likely alternatives? “I’m totally supportive of moving toward a wood-based fuel if it can be proven to be a reliable source of fuel, a cost-effective source of fuel, and if it can integrate reasonably into our existing system here."[39]

Hawaii: Hu Honua Station

In August 2008, the Hu Honua Bioenergy facility opened on the Big Island of of Hawaii. The 24 MW plant was previously coal fired, but is planned to burn locally-grown sustainable crops and plant waste that would otherwise be sent to landfills. The plan is to supply about 7-10 percent of the island's power, or enough for about 18,000 homes. According to the developers of the plant, the conversion will help Hawaii meet its goal of having 20 percent of its energy production come from renewable resources by 2020. Neither the state nor the county governments have officially approved this project and the plant has not been in operation since January 1, 2005.[40][41]

Illinois: The Eastern Illinois University Power Plant

The Eastern Illinois University Power Plant is a coal-fired plant built in 1925. In 2009 the University submitted permits for a new biomass facility to replace the coal plant, including possible wind turbines. The new plant will be a “biomass gasifier” that will fill University heating and cooling needs by burning nontreated wood chips obtained as lumber industry by-products. The proposal is the largest project in campus history in terms of the dollar amount.[42]

In May 2010, the University of Illinois pledged to stop using coal within seven years as part of a plan to reduce energy use and cut carbon emissions: the Illinois Climate Action Plan, finalized that month. The plan was developed by the campus Sustainability Council. It was submitted to the American College and University Presidents' Climate Commitment, signed by more than 600 schools. The UI is the first Big Ten school to formally submit a climate plan.[43]

To meet its goals, UI is considering alternative fuels that could be used by University of Illinois Abbott Power Plant or another central generation facility, officials said. University buildings – which account for 85 percent of the campus's energy use – are primarily heated by steam produced at Abbott. The plant also produces electricity as a byproduct, with the UI buying additional electricity from private suppliers. Abbott runs primarily on natural gas and coal, with the fuel mix decided by market costs, according to UI officials. The sustainability team concluded that Abbott's natural gas capacity can provide almost enough steam to meet campus demand by itself and should be able to do so in a few years if conservation trends continue. The campus burned 94,171 tons of coal in fiscal 2009, although that figure has dropped 30 percent in fiscal 2010 so far, said Tom Abram, sustainability coordinator in UI Facilities and Services.[43]

The settlement requires Duke Energy to repower Units 1 and 3 at Gallagher with natural gas or shut them down, and to install scrubbers at Units 2 and 4, reducing sulfur dioxide emissions 86 percent when compared to 2008 emissions. Duke will also pay a $1.75 million penalty and spend $6.25 million on various environmental mitigation projects.[44]

Indiana: IPL to retire Eagle Valley and two units at Harding Street; replacing capacity with new natural gas plant

In May 2013, Indianapolis Power & Light, a subsidiary of AES, announced that the Eagle Valley Station will be retired, with a 650 MW combined cycle gas plant to be constructed at the same site by 2017. At the same time IPL announced plans to retire or refuel two of the three coal-fired units at the Harding Street Station (Units 5 and 6, but not Unit 7).[45]

In July 2009, the Jasper Municipal Electric Utility announced it was considering converting its coal-fired power plant to burn waste wood. The 15MW plant has been shut down for all but a few weeks this year, because it has become too expensive to operate. A conversion project would cost an estimated $11 million, but the city could see a profit of about $1 million each year.[46]

In 2011 Richmond Power & Light of Indiana said it plans to switch its 100-MW Whitewater Valley Generating Station in Richmond, Indiana to burn gas produced from solid waste by the spring of 2013. Only one of Whitewater Valley's two units -- a 66-MW unit installed in 1972 -- is expected to be retrofitted for gasification; the other 34-MW unit will be shut down within the same timeframe. The conversion is estimated to cost $150 million to $160 million. The city is signing a contract with Cate Street Capital of Delaware, which is expected to finance and operate the new venture.[48]

On November 14, 2013, TVA announced that it would retire Paradis Fossil Plant units 1 and 2. The board also approved construction of a new gas-fired plant at a cost not to exceed $1.12 billion. The time frame for the retirements was left to the discretion of the CEO.[51][52]

In September 2009, NRG Energy announced it was replacing some coal at Big Cajun II with switchgrass and sorgham. The company said the project could eventually lead to commercial-scale biomass fuel projects as a means of dealing with potential greenhouse gas regulations.[53]

In November, 2009, NRG Energy announced that it will close the Somerset Power Generating Station on January 2, 2010. A company spokesman cited "market forces" and a "requirement that we close down or repower [by] September of 2010." NRG plans to convert the plant from burning coal to a plasma gasification process, which breaks down coal into its component parts before converting it into energy. No timetable for that conversion has been announced.[54]

Opponents of the Somerset plant, including the Conservation Law Foundation, the Massachusetts Clean Air Coalition, and the Toxics Action Center, expressed optimism that the conversion to gasification would prove to be infeasible. "Shutting down Somerset for an indefinite period shows that this old coal-fired plant is not necessary for reliability and undermines the likelihood that the coal gasification project will move forward," said Shanna Cleveland, staff attorney for CLF.[55]

In September 2010, Northern States Power Company's Black Dog Generating Station was shut down following a fire and subsequent explosion at the plant’s 108-megawatt Unit 3 burner. Workers at the plant noticed smoldering in a coal hopper and notified Burnsville emergency services. Response crews were on the scene when contents of the bin fully ignited, resulting in an explosion that blew out some 200 feet of the plant’s west-facing wall. Three firefighters sustained minor injuries, none of the plants employees were hurt. The power plant will remain offline as officials from Xcel, the Federal Occupational Safety and Health Administration, and Burnsville Fire Department determine the cause of the blast. Company officials stated that services will not be interrupted because power is being routed from an alternate source to serve customers.[56]

Xcel currently has a proposal pending with the Minnesota Public Utilities Commission to retire Black Dog's two remaining coal-fired boilers (units 3 and 4), converting them to natural gas combined-cycle units by 2016.[56]

In September 2003, Xcel Energy announced plans to convert its Riverside and High Bridge coal plants to natural gas. The move came in response to an emissions reduction bill passed in 2001 by the Minnesota Legislature, allowing any utility company in the state to convert its coal plants to natural gas and then recover the costs of conversion through rate increases.[58] The facilities were part of a $1 billion upgrade of Xcel power plants in Minnesota. The new 570 MW High Bridge Plant went online in May 2008 and the new 511 MW Riverside Plant in April 2009.[59][60]

In October 2003, the Public Service Company of New Hampshire (PSCNH) filed a plan to convert Unit 5 of the coal-fired Schiller Station to burn woody biomass. The $75 million dollar project broke ground in December 2004 and went online in December 2006.[63][64][65]

The unit burns 400,000 to 450,000 tons of wood per year to power approximately 50,000 homes. Using biomass in this unit reduces coal use at the plant by over 30 percent, or about 130,000 tons per year.[63][64] However, the Schiller Station still burned 421,670 tons of coal in 2008, two years after the plant began operating.[66]

Compared to the previously coal-fired Unit 5, emissions estimates for the biomass burner are 70 percent lower for nitrogen oxides, 95 percent lower for sulfur dioxide, and 90 percent lower for mercury.[64] These reduced emissions help the Schiller Station meet the requirements of the New Hampshire Clean Power Act.[63]

In June 2012 RC Cape May Holdings LLC said it will shut down one coal-fired unit at the B.L. England plant in Marmora and retrofit a second coal-fired unit to a natural gas turbine and will re-fuel a third, oil-burning unit with natural gas. The agreement resolves violations of the Clean Air Act that occurred when the plant was under the ownership of Atlantic Electric, Conectiv, and Pepco Holdings Co., who did not make pollution-control upgrades as required by the federal Clean Air Act when adding significant upgrades to operational features of the plant.[68]

The agreement calls for the cessation of operation of coal-fired Unit 1 by fall 2013; until that occurs, the company must take steps to minimize emissions from this unit. Unit 2, which currently burns coal, and Unit 3, which burns fuel oil and only operates during peak demand periods, are to be converted to natural gas by May 2016. Unit 2 is to be shut down by May 2015 to allow for the conversion.[68]

According Bill O’Sullivan, administrator of air quality for the New Jersey Department of Environmental Protection, the Howard Down Generating Station, a 25 MW coal plant operated by Vineland Municipal Electric in New Jersey, was scheduled to replace its last coal-fired generator with natural gas in 2010.[69]

In December 2009, Cornell University switched its facility to primarily natural gas. By mid-2011 Cornell will eliminate all coal use on campus, helping it meet its Climate Action Plan, which seeks to reduce the school's effective greenhouse gas emissions from 319,000 metric tons (CO2 equivalent emissions) to net zero level by 2050 through "green" development, energy conservation, alternative energy sources, and carbon offsetting. Natural gas, while still a fossil fuel, is said by the university to be a step forward in achieving this goals.[70]

North Carolina: Progress Energy plants

Progress Energy Corp. announced in August 2009 that it will shut down the three-unit 397-megawatt Lee Steam Plant near Goldsboro, N.C., and apply for regulatory approval to replace the coal generation with 950 megawatts of natural gas-fired generation.[71][72] North Carolina State regulators approved the plan on October 1.[73]

On December 1, 2009, Progress Energy Carolinas announced that by the end of 2017 it would permanently close all of its North Carolina coal plants without sulfur dioxide scrubbers. The 11 units at L.V. Sutton, Cape Fear, Weatherspoon, and Lee total almost 1,500 megawatts and represent about a third of the utility's coal-fired power generation in N.C. The retirement plan includes the following:

Lee is still scheduled for retirement in 2013.

Sutton is slated for closure in 2014. Progress hopes to replace it with a natural gas-fired power plant.

Cape Fear and Weatherspoon will be shut down between 2013 and 2017. The company is considering converting 50 to 150MW of the total capacity to burn wood waste.

The closure plan was filed in response to a request by the N.C. Utilities Commission, which ordered Progress to provide its retirement schedule for "unscrubbed" coal-fired units in North Carolina. The request was a condition of the commission's approval of Progress' plan to replace Lee's coal-fired generation with a 950-MW natural gas plant.[74][75]

On April 1, 2009, First Energy announced that it is retrofitting the R.E. Burger power plant in eastern Ohio to produce electricity from woody biomass instead of coal, which would make it one of the largest such facilities in the U.S. The conversion will cost about $200 million. FirstEnergy had faced an April 2 deadline to either close the plant, install $330 million in pollution controls, or convert to biomass.[76]

The project will produce over 300 MW of electricity, enough to power 190,000 houses. It is scheduled for completion in 2012.[77]

In November 2010 First Energydecided not to pursue the biomass option. The company cited the reason as an economic one, stating it was too expensive to undertake. The boilers will be permanently shut down by December 31, 2010.[78]

On June 9, 2011, AEP announced that, based on impending EPA regulations as proposed, AEP’s compliance plan would retire nearly 6,000 megawatts (MW) of coal-fueled power generation; upgrade or install new advanced emissions reduction equipment on another 10,100 MW; refuel 1,070 MW of coal generation as 932 MW of natural gas capacity; and build 1,220 MW of natural gas-fueled generation. The cost of AEP’s compliance plan could range from $6 billion to $8 billion in capital investment through the end of the decade. AEP’s current plan for compliance with the rules as proposed includes permanently retiring five of its coal-fueled power plants.[49]

In addition, six other plants which will reduce their power output:[79]

On January 14, 2010 it was announced that Portland General Electric will be closing its 601 MW Boardman Plant twenty years ahead of schedule. The plant will close in 2020 instead of 2040. The plant was originally going to invest more than a half billion dollars in pollution controls (scrubbers) by 2017 to comply with EPA and state clean air regulations, then keep it running until 2040.

Instead, the company wants regulators to allow it to make a $45 million investment by 2011 to partially clean up its emissions of mercury and oxides of nitrogen, then operate the plant until 2020.[80] The Oregon Sierra Club and Friends of the Columbia Gorge argue, that while a 2020 close date is better than a 2040 closure, it is still more economical for the plant to shut its doors in 2014. [81]

On February 1, 2010 it was announced that PGE was considering using biomass to continue operating the plant after it ends its use of coal in the future. PGE is said to be considering if it can replace all of the millions of tons of coal it burns every year at Boardman with plant based material that has been pre-treated through a process called torrefaction. While still in experimental phases, torrefaction produces a substance similar to coal, and is also energy intensive to produce. Critics on the other hand cite that no commercial size torrefaction facilities exist and it is still not clear how much carbon will be used in the process of torrefaction.[82]

Pennsylvania: Penn State University to Convert Plant to Natural Gas

Penn State's West Campus Steam Plant consumes about 7,500 tons of coal per year, and produces about 20,000 MWh per year, or 7% of the campus's electricity demand - as well as about 175 tons of steam per hour, which is used for heating campus buildings. Built in 1929, the plant holds four boilers, and burns coal from Clarion County, Pennsylvania. (Several solar panels on the roof of the Office of Physical Plant building only produce enough electricity to power several rooms within that building.)

Penn State buys 89% of its electricity from Allegheny Energy, which in turn gets 95% of its electricity production from coal-fired power plants. In an interview in 2003, Paul Ruskin, the spokesperson for the Office of Physical Plant, stated that "we would like to have totally non-polluting sources, but they're not out there yet."[83][84][85]

On January 21, 2011 Penn State announced that they would be converting their steam plant to burn natural gas. Burns and McDonnell was awarded a contract of $25 million to $35 million to convert the college's coal-fired steam plant to natural gas in a move university officials stated would reduce carbon emissions. The university has been considering its options for upgrading the coal-fired plant since 2009 in anticipation of stiffer EPA regulations.[86]

In December, 2010, Kennecott Utah Copper announced that it would repower units 1-3 of its Utah Smelter power plant to run on natural gas. However, unit 4 of the plant will continue to be powered by coal. [87]

In Feb. 2011, Dominion Virginia Power said it could reopen its 63 MW Altavista Power Station as a biomass electricity plant by 2013, and is starting the approval process. In Fall 2010, Dominion placed the Altavista station on “cold reserve status,” meaning it could be restarted if needed. At the time, Dominion was studying whether to convert the plant to a biomass facility. The study suggested that a biomass facility would be competitive economically against natural gas plants. If the town of Altavista grants Dominion’s special use permit request, the company said it will seek a new air permit and approval from the State Corporation Commission.[88]

In April 2011, Dominion Resources announced that its subsidiary Dominion Virginia Power, has decided use biomass instead of coal in three of its power stations: Altavista Power Station, Hopewell Power Station and Southampton Power Station. The plants will mainly use waste wood left from timbering operations as a source of fuel. If approved by the local authority and the regulators will begin production from the converted units in 2013. The units can presently produce 63 megawatts (MW) power each and are only used when demand is at its peak. After conversion, these units will produce 50 MW each.[89]

Virginia: TVA to shutter the coal-fired Allen Fossil Plant and built a combined-cycle natural gas plant

In April 2014, the TVA board of directors voted to retire the Allen Fossil Plant, and build a new, combined-cycle natural gas plant nearby. The new gas plant will be 1,000 MW and operable by the end of 2018.[90]

On February 26, 2009, Speaker of the House Nancy Pelosi and Senate Majority Leader Harry Reid directed the Architect of the Capitol, Stephen T. Ayers, to switch the Capitol Power Plant to run on natural gas.[91] The letter came just four days before a planned protest at the plant, where several thousand demonstrators gathered to protest global warming.[92] The announcement was viewed by many as a victory for grassroots activism, but the rally went forward to call attention to coal issues around the country.[93]

In April 2009, Ayers responded that he was shifting the plant's fuel source to natural gas. As part of the transition, he requested $10 million to redesign and convert the second burner to use natural gas, a process that could be complete as early as November 2010. Ayers noted that the plant would continue to use coal as a backup fuel during abnormally cold weather or equipment outages. [94]

In October 2008, Xcel Energy announced plans to spend over $55 million to convert the last remaining coal-fired unit at its Bay Front Power Plant to biomass. The conversion will enable the facility to use 100 percent biomass in all three boilers. Xcel submitted an application to the Public Service Commission of Wisconsin in February 2009. If approved, construction could begin in 2010 and operation in late 2012.[95][96]

The facility primarily burns waste wood from area forest harvesting operations. The existing biomass incinerators burn about 200,000 tons of waste wood each year. When the project is completed, the plant will use another 185,000 to 250,000 tons per year and will be capable of generating enough electricity for 40,000 homes. According to Xcel, the project will reduce emissions of nitrogen oxides by approximately 50 percent, sulfur dioxides by over 85 percent, and particulate matter by 90 percent.[95][96]

In August 2008, Wisconsin Governor Jim Doyle announced that two aging coal plants, the Charter Street Heating Plant and the Capitol Heat and Power Plant, both located in Dane County, will be shut down and replaced with cleaner systems. The decision followed legal action and grassroots protests and lobbying by members of the Sierra Club, students at the University of Wisconsin, and other activists. August 2008[98]

In 2010, Capitol Heat and Power stopped burning coal. Instead, the downtown Madison plant will use natural gas to heat and cool office buildings in the area.[99]

In February 2009, Governor Jim Doyle announced that the University of Wisconsin's Charter Street Heating Plant will phase out coal. Under the plan, one of five boilers at the plant will be converted to burn biomass, including cornstalks, switch grass, and wood chips, in an effort to generate 25 percent of the state's energy from renewable resources by the year 2025. Four coal boilers will be converted to burn natural gas. The project, which is estimated to cost $200 million to $300 million, will eliminate the burning of over 100 tons of coal per year.[100][101]

In June 2008, DTE Energy announced plans to purchase the E.J. Stoneman Power Plant from Integrys and convert its 50MW of coal capacity to burn wood waste.[103] At the time of the announcement, DTE hoped begin the conversion in 2009.[104] Commercial operation of the 40 MW biomass facility began on Oct. 8, 2010.[105]

In early May 2011, We Energies announced that it planned to take the initial steps toward converting the Valley Power Plant to natural gas from coal.

In March 2011, Clean Wisconsin and Sierra Club filed petitions with the Wisconsin Department of Natural Resources and the U.S. Environmental Protection Agency, contending that the Valley Power Plant's air permit, issued by the DNR, violates the Clean Air Act.[106]

In March 2011, the State of Wisconsin announced that the Waupun Correction Central Heating Plant in Waupun, Wisconsin would be converted to a natural gas burning facility. The plant provides power to the Waupun maximum security prison. A time line for the conversion was not immediately set. The cost of the conversion was estimated at $7 million by the Governor Walker's proposed budget for 2011-2013.[107][108]

In its April 2012 filing, PacifiCorp announced its intention to stop burning coal at Naughton Power Plant unit 3. PacifiCorp is debating converting the plant to natural gas, primarily to serve summer peak load in Utah and Wyoming.[109]

Ontario, Canada

As a result of a commitment to completely phase out the province's coal plants by 2014, the Ontario government is converting the 310-megawatt Thunder Bay coal plant to natural gas. The following other plants were scheduled as of 2007:[110][111]

In September 2009, Ontario Power Generation announced it will shut down four of its 15 coal-fired power plants in late 2010. The closures include two of eight units at Nanticoke Generating Station, and two of four units at Lambton. The four plants represent about 2,000 megawatts of total generation capacity. The closure of the four units, in addition to the 2005 closure of Lakeview Generating Station in 2005, will reduce the Canadian province's coal capacity by 40 percent. OPG said it would continue to assess converting its remaining 11 units to other types of fuel such as biomass, beginning with the conversion of Atikokan Generating Station by 2012.[112][113]